text: At the beginning of the run, a mixture of solutes to be separated is applied to the column, under conditions selected to promote high retention.  The higher-affinity solutes are preferentially retained near the head of the column, with the lower-affinity solutes moving farther downstream.  The fastest moving component begins to form a pure zone downstream.  The other components also begin to form zones, but the continued supply of the mixed feed at head of the column prevents full resolution.